Field
The described technology generally relates to a rechargeable battery.
Description of the Related Technology
With the advancement of mobile device technology, demand for rechargeable batteries has been increasing. A rechargeable battery differs from a primary battery in that it can be repeatedly charged and discharged, while the latter cannot be recharged.
One important aspect in manufacturing rechargeable batteries is energy density because these batteries are embedded in small electronic devices to be used as the power source.
In this case, the volume or capacity and form factor of the power source are determined in part by the size of the electronic device. According to a recent trend of shrinking information technology (IT) devices, the size of the power source is also becoming smaller.
However, the market demand is that the rechargeable battery last longer with increased capacity despite a reduced size. Accordingly, unnecessary space in the rechargeable battery should be reduced to make a compact size. Furthermore, with the development of flexible electronic devices, the rechargeable battery also needs to be flexible.
A pouch type of rechargeable battery having such characteristics has been developed. The pouch type of rechargeable battery typically includes i) an electrode assembly formed by stacking a positive electrode, a separator, and a negative electrode to perform charging and discharging operations, ii) a pouch in which the electrode assembly is accommodated, and iii) electrode tabs through which the electrode assembly is drawn out of the pouch.
An electrolyte solution is provided in an empty space between the electrode assembly and the pouch, and a vacuum state is maintained inside the rechargeable battery to minimize an overall volume.
However, when the flexible rechargeable battery is exposed to repeated bending, loosely coupled parts can break as bending stress is applied to the pouch type of rechargeable battery.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.